If you go into LOP lean mode .. after the last cylinder peaks, push and hold the right button .. the right hand number will be the 'spread' in gph between the 1st and last cylinders to peak.
GAMIs will give you 0.5 or less (probably less).
OK, did a test flight last night. I'm getting a 0.2 spread, so GAMI's probably won't do much. I leaned down to 85LOP with no roughness, but was down to 2,000RPM by then so didn't go any further.
I'll check the baffles as Joe suggested, but likely if I want to go faster... I need a faster airplane :-D